i answered a question simular to this yesterday
heres my answer….................
i felt very welcome at first .. it was great .. but now that the mods have relaxed their watchover…..people are learning the little known fact that jellyfish have stingers . and can attack in groups .
Jellyfish Sting Symptoms
Symptoms include an intense, stinging pain, itching, rash, and raised welts.
The progressive effects of a jellyfish sting may include nausea, vomiting, diarrhea, lymph node swelling, abdominal pain, numbness/tingling, and muscle spasms.
Severe reactions can cause difficulty breathing, coma, and death.
A sting from a box jellyfish or other venomous types of jellyfish can cause death in minutes.
Prevention
Wear protective clothing (gloves, wet suits, dive skins) when swimming in jellyfish-infested areas. Avoid picking up dead jellyfish. Dead jellyfish may still have live nematocysts that can still release toxins (even after they have dried up).
Avoid going into known jellyfish-infested areas. If you do, know what type of jellyfish are common to the area
Be prepared to treat a jellyfish sting. Have a basic first aid kit (make sure it has an oral antihistamine in the kit) prepared and bring it with you.
Take a course in basic first aid before heading to the beach, snorkeling, swimming, or scuba diving.
In the evening or at night when swimming, snorkeling, or scuba diving, take care to look for jellyfish on the surface of the water.
Expel air from the alternate air source while ascending during scuba diving to disperse any jellyfish directly above you.
Educate yourself as to the type of jellyfish that may be in the waters in which you are swimming, snorkeling, or scuba diving
Bring Safe Sea Jellyfish After Sting® pain relief gel in case you do get stung.
Do not swim in waters where large numbers of jellyfish have been reported. Wearing a wet suit or Lycra dive skin can prevent stings.
If you have a known insect sting allergy carry an allergy kit, which contains injectable epi-pens (epinephrine, adrenaline). Make sure those with you know how to administer the epi-pen in case you are unable to do so.
Do not touch any marine life while swimming, snorkeling, or scuba diving. Most marine animals have a protective coating that when touched, is rubbed off when and exposes the animal to bacteria and parasites; moreover, touching, “playing,” or moving marine animals is stressful for them. Corals are easily damaged when touched and the area if the coral touched by hands, fins, or the body will die. To protect the ocean environment, when swimming, snorkeling, or scubadiving look, don’t touch, and leave only bubbles.